Photovoltaic modules currently enjoy broad commercial use. For example, in terrestrial applications, photovoltaic modules are typically used to power remote electronic equipment such as radio towers, microwave repeater stations, and navigation buoys. Photovoltaic modules are also used to generate power for on-grid applications. In certain applications, photovoltaic modules, such as individual photovoltaic cells, may be wired together to form an array so that increased power may be produced. However, a need exists for photovoltaic modules that provide increased power at greater efficiency than currently available.
One source of inefficiency, and decreased power output, is a decrease in performance of photovoltaic modules at elevated temperatures. It is known that the operating voltage, and therefore power output, of photovoltaic materials decreases as the temperature of the material increases. The effect is approximately linearly proportional to the inverse of the material's change in temperature. It is also known that photovoltaic modules typically operate between 20-30 degrees Celsius higher than the ambient air temperature. This increase in temperature above ambient produces a 5-20% reduction in operating power, depending on the particular photovoltaic cells or materials used in the module.
This reduction in operating power with increased temperature affects many different configurations of photovoltaic modules, such as concentrating photovoltaic collectors and flat-plate modules. Concentrating collector modules use reflective or refractive materials to focus sunlight onto a smaller surface area of photovoltaic cells or materials. Flat plate modules are the most commonly used photovoltaic modules and are typically manufactured as flat assemblies of solar cells encapsulated between glass and suitable rear surface. Both types of modules suffer from reduced power output at elevated temperature. Hence, a need exists for a passive cooling system for photovoltaic modules which may be fabricated in a cost-effective manner.